How's my line here with 88? (6 max)

I have trouble with these mid PP where I'm the preflop raiser, I find it hard to tell where I'm at against LP players.

River bet was awfully suspicious, I probably should have called for just 1 more bet. But was my turn bet ok? Or should I have checked behind and c/c the river? Played only 20+ hands or so with villain, but so far he seems like a calling station.

Party Poker 0.50/1 Hold'em (6 max, 4 handed) FTR converter on zerodivide.cx

Preflop: Hero is BB with 8[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/spade.gif[/img].
<font color="#666666">2 folds</font>, SB completes, <font color="#CC3333">Hero raises</font>, SB calls.

Flop: (4 SB) T[img]/images/graemlins/spade.gif[/img], T[img]/images/graemlins/diamond.gif[/img], J[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
SB checks, <font color="#CC3333">Hero bets</font>, SB calls.

Turn: (3 BB) 5[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
SB checks, <font color="#CC3333">Hero bets</font>, SB calls.

River: (5 BB) 9[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets</font>, Hero folds.

SB made the straight here? Calling all the way down with a gutshot? I'm thinking KQ is unlikely, even a calling station would open-raise KQ from SB would they not? Or maybe he was slowplaying Tx all along... I'm baffled, I have no clue where I am at with this hand. Maybe he has Jx, but why bet now when he has been c/c all along?